My 1666 has an almost silent mechanical E unit and runs and pulls very well! 
Yeah, isn’t that odd? I’ve got a 2065 with an E-unit that’s almost silent and then I’ve got other post-wars with E-units you can hear across the room.
Hey, as long as they work, right?
Yes the Sante Fe Warbonnets buzz like a chain saw!They work just fine though.